Although it is difficult to link specific weather events with global warming, the rise of global temperature may in turn lead to wider changes, including glacier retreat, Arctic contraction and global sea level rise. Changes in precipitation and precipitation patterns may lead to floods and droughts. The frequency and intensity of extreme weather events may also change. Other impacts may include the change of agricultural output, the increase of new trade routes, the decrease of river flow in summer, species extinction and the expansion of vector range.

Some impacts on the natural environment and human life have been at least partly attributed to global warming. A 200 1 report of IPCC shows that glacier retreat, ice shelf destruction such as Larsen ice shelf, sea level rise, rainfall pattern change and the increase in intensity and frequency of extreme weather events are all part of the reasons for global warming. Although the overall pattern, intensity and frequency are expected to change, it is difficult to attribute specific events to global warming. Other expected impacts include water shortage in some areas, increased precipitation in other areas, changes in snow cover in mountainous areas, and adverse health effects of rising temperatures.